Snapshot management in hierarchical storage infrastructure

ABSTRACT

Embodiments of the present invention disclose a method, computer program product, and system for snapshot management in a storage infrastructure. A computer identifies one or more snapshots within layers of the storage infrastructure. The computer determines one or more relationships of the one or more identified snapshots of the storage infrastructure. The determined relationships include, at least in part, relations of one or more entities included in the one or more snapshots to additional one or more entities in the one or more snapshots of the storage infrastructure. The computer identifies the one or more duplicate snapshots by utilizing the one or more determined relationships of the one or more identified snapshots. The computer consolidates the one or more identified duplicate snapshots in the storage infrastructure. In another embodiment, the computer identifies one or more inconsistent snapshots, and consolidates the one or more inconsistent snapshots in the storage infrastructure.

FIELD OF THE INVENTION

The present invention relates generally to the field of data management,and more particularly to snapshot management in hierarchical storageinfrastructure.

BACKGROUND OF THE INVENTION

Information Technology (IT) infrastructure environments can include ahierarchical storage infrastructure which can be used to create andstore snapshots in different layers of hierarchical storageinfrastructure. IT infrastructure environments utilize servers andserver virtualizers in conjunction with storage area networks (SAN) andstorage virtualizers to provide the capability to create and managesnapshots. A SAN provides access to consolidated, block level datastorage and can be used to make storage devices (i.e. disk arrays)accessible to servers so that the storage devices can appear to belocally attached to the operating system. A snapshot is a usable copy ofa defined collection of data that contains an image of how the dataappeared at a point in time. In some examples, snapshots may also bereferred to as point in time copies. Infrastructure environments arebecoming increasingly complex, which leads to an increasing importanceof snapshots.

SUMMARY

Embodiments of the present invention disclose a method, computer programproduct, and system for snapshot management in a storage infrastructure.A computer identifies one or more snapshots within layers of the storageinfrastructure. The computer determines one or more relationships of theone or more identified snapshots of the storage infrastructure. Thedetermined relationships include, at least in part, relations of one ormore entities included in the one or more snapshots to additional one ormore entities in the one or more snapshots of the storageinfrastructure. The computer identifies the one or more duplicatesnapshots by utilizing the one or more determined relationships of theone or more identified snapshots. The computer consolidates the one ormore identified duplicate snapshots in the storage infrastructure. Inanother embodiment, the computer identifies one or more inconsistentsnapshots, and consolidates the one or more inconsistent snapshots inthe storage infrastructure.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a functional block diagram of a data processing environment inaccordance with an embodiment of the present invention.

FIG. 2 is a flowchart depicting operational steps of a program formigrating and consolidating snapshots in an IT infrastructureenvironment, in accordance with an embodiment of the present invention.

FIG. 3 depicts a block diagram of components of the computers of FIG. 1in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

Embodiments of the present invention recognize that multiple copies ofthe same data in different layers of an IT infrastructure environmentwastes space. In an example, snapshots of data in IT infrastructureenvironments can cause a large amount of repetitive data, which willlead to wasted space. Users and administrators of the IT infrastructureenvironment may not be aware of existing snapshots throughout the layersof the IT infrastructure environment. In an example, an administratormay take a snapshot of a virtual machine, but is not aware a user haspreviously taken a snapshot of certain components inside the virtualmachine. Also, users and administrators may not be aware of through whatmeans or location snapshot data is stored or protected. Embodiments ofthe present invention also recognize manually collecting and joining allexisting information regarding snapshots in all layers of an ITinfrastructure environment can become a time consuming process.

As will be appreciated by one skilled in the art, aspects of the presentinvention may be embodied as a system, method or computer programproduct. Accordingly, aspects of the present invention may take the formof an entirely hardware embodiment, an entirely software embodiment(including firmware, resident software, micro-code, etc.) or anembodiment combining software and hardware aspects that may allgenerally be referred to herein as a “circuit,” “module” or “system.”Furthermore, aspects of the present invention may take the form of acomputer program product embodied in one or more computer-readablemedium(s) having computer readable program code/instructions embodiedthereon.

Any combination of computer-readable media may be utilized.Computer-readable media may be a computer-readable signal medium or acomputer-readable storage medium. A computer-readable storage medium maybe, for example, but not limited to, an electronic, magnetic, optical,electromagnetic, infrared, or semiconductor system, apparatus, ordevice, or any suitable combination of the foregoing. More specificexamples (a non-exhaustive list) of a computer-readable storage mediumwould include the following: an electrical connection having one or morewires, a portable computer diskette, a hard disk, a random access memory(RAM), a read-only memory (ROM), an erasable programmable read-onlymemory (EPROM or Flash memory), an optical fiber, a portable compactdisc read-only memory (CD-ROM), an optical storage device, a magneticstorage device, or any suitable combination of the foregoing. In thecontext of this document, a computer-readable storage medium may be anytangible medium that can contain, or store a program for use by or inconnection with an instruction execution system, apparatus, or device.

A computer-readable signal medium may include a propagated data signalwith computer-readable program code embodied therein, for example, inbaseband or as part of a carrier wave. Such a propagated signal may takeany of a variety of forms, including, but not limited to,electro-magnetic, optical, or any suitable combination thereof. Acomputer-readable signal medium may be any computer-readable medium thatis not a computer-readable storage medium and that can communicate,propagate, or transport a program for use by or in connection with aninstruction execution system, apparatus, or device.

Program code embodied on a computer-readable medium may be transmittedusing any appropriate medium, including but not limited to wireless,wireline, optical fiber cable, RF, etc., or any suitable combination ofthe foregoing.

Computer program code for carrying out operations for aspects of thepresent invention may be written in any combination of one or moreprogramming languages, including an object oriented programming languagesuch as Java®, Smalltalk, C++ or the like and conventional proceduralprogramming languages, such as the “C” programming language or similarprogramming languages. The program code may execute entirely on a user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).

Aspects of the present invention are described below with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems) and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer program instructions. These computer program instructions maybe provided to a processor of a general purpose computer, specialpurpose computer, or other programmable data processing apparatus toproduce a machine, such that the instructions, which execute via theprocessor of the computer or other programmable data processingapparatus, create means for implementing the functions/acts specified inthe flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in acomputer-readable medium that can direct a computer, other programmabledata processing apparatus, or other devices to function in a particularmanner, such that the instructions stored in the computer-readablemedium produce an article of manufacture including instructions whichimplement the function/act specified in the flowchart and/or blockdiagram block or blocks.

The computer program instructions may also be loaded onto a computer,other programmable data processing apparatus, or other devices to causea series of operational steps to be performed on the computer, otherprogrammable apparatus or other devices to produce acomputer-implemented process such that the instructions which execute onthe computer or other programmable apparatus provide processes forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks.

The present invention will now be described in detail with reference tothe Figures. FIG. 1 is a functional block diagram illustrating dataprocessing environment 100, in accordance with one embodiment of thepresent invention.

Data processing environment 100 includes IT infrastructure environment110, I/O system 140, and hierarchical snapshot manager 150. In oneexemplary embodiment, IT infrastructure environment 110, I/O system 140,and hierarchical snapshot manager 150 can be desktop computers,specialized computer servers, or any other computer systems known in theart. In certain embodiments, IT infrastructure environment 110, I/Osystem 140, and hierarchical snapshot manager 150 represent computersystems utilizing clustered computers and components (e.g., databaseserver computers, application server computers, etc.) acting as a singlepool of seamless resources when accessed by elements of data processingenvironment 100. In general, IT infrastructure environment 110, I/Osystem 140, and hierarchical snapshot manager 150 are representative ofany electronic device or combination of electronic devices capable ofexecuting machine-readable program instructions, as described in greaterdetail with regard to FIG. 3. In one embodiment, IT infrastructureenvironment 110 includes storage devices organized in a hierarchicalstructure corresponding to various layers of the IT infrastructureenvironment. In an embodiment, the elements of data processingenvironment 100 can communicate through network connections such as alocal area network (LAN), a telecommunications network, a wide areanetwork (WAN) such as the Internet, or a combination of the three, andinclude wired, wireless, or fiber optic connections. In another example,I/O system 140 and hierarchical snapshot manager 150 can be locatedwithin IT infrastructure environment 110.

IT infrastructure environment 110 is an exemplary depiction of anenvironment of a hierarchical storage infrastructure, which includeslayer 1 snapshot manager 120 and layer 2 snapshot manager 130. In oneembodiment, layer 1 snapshot manager 120 and layer 2 snapshot manager130 control the creation, deletion and storage of snapshots in ITinfrastructure environment 110. Each layer of IT infrastructureenvironment 110 capable of taking snapshots has a snapshot manager (i.e.layer 1 snapshot manager 120 and layer 2 snapshot manager 130). Layer 1snapshot manager 120 and layer 2 snapshot manager 130 are instances ofsnapshot management systems each corresponding to a certain layer of ITinfrastructure environment 110. In one embodiment, layer 1 snapshotmanager 120 and layer 2 snapshot manager 130 can be representations ofthe same type of snapshot management system (including the samecomponents) residing on different layers of IT infrastructureenvironment 110, wherein each snapshot manager includes datacorresponding to the layer of IT infrastructure environment that thesnapshot manager resides on. In another example, IT infrastructureenvironment 110 can include more than two layers capable of takingsnapshots. In such an example, a snapshot manager can exist on eachlayer of IT infrastructure environment 110 capable of taking snapshots.In one embodiment, layer 1 snapshot manager 120 includes snapshot engine122 and snapshot data manager 124, and layer 2 snapshot manager 130includes snapshot manager 132 and snapshot data manager 134. Snapshotengine 122 and 132 control the snapshot creation and deletion aspects ofsnapshot manager 120 and 130 respectively. Snapshot data manager 124 and134 maintain snapshot metadata, and snapshot data corresponding to, atleast in part, snapshotted entities in IT infrastructure environment110, a snapshot time, and a storage location for a snapshot. In oneembodiment, snapshot engine 122 and 132 communicate with respectivesnapshot data managers 124 and 134 to share information about snapshots(i.e. creation and deletion of snapshots), which snapshot data managercan then store.

In one embodiment, I/O system 140 keeps track of snapshot updates ofstorage entities in the layers of IT infrastructure environment 110, andparent storage entities that correspond to other storage entities in theIT infrastructure environment. I/O system 140 can communicate withsnapshot data manager 124 and 134 to share information corresponding tosnapshots of entities in IT infrastructure environment 110.

Hierarchical snapshot manager 150 includes hierarchical snapshot engine152, hierarchical asset history 154, hierarchical snapshot data manager156 and hierarchical snapshot management program 200. In one embodiment,hierarchical snapshot manager 150 can access snapshots and snapshotinformation throughout all layers of IT infrastructure environment 110.Hierarchical snapshot engine 152 is responsible for controlling themigration of snapshots throughout the layers of IT infrastructureenvironment 110. Hierarchical snapshot engine 152 can communicate withsnapshot engine 122 and 132 to perform snapshot configuration changes,such as deleting, creating, or restoring snapshots. In one embodiment,hierarchical asset history 154 is a database for collecting and storinginformation corresponding to all snapshots from all snapshot managers(i.e. layer 1 snapshot engine 120 and layer 2 snapshot engine 130) in ITinfrastructure environment 110. The snapshot information in hierarchicalasset history 154 includes, at least in part, a layer in ITinfrastructure environment 110 corresponding to the snapshot, snapshotsize, snapshot time, and snapshot storage information. Hierarchicalasset history 154 can be implemented with any type of database storagecapable of storing data which may be accessed and utilized by elementsof IT infrastructure environment 110, and I/O system 140, such as adatabase server, a hard disk drive, or flash memory. In an embodiment,layer 1 snapshot manager 120 or layer 2 snapshot manager 130 can notifyhierarchical asset history 154 of changes to snapshot informationthrough communication with I/O system 140. Hierarchical snapshot engine152 can communicate with hierarchical asset history 154 in order toreflect actions taken by the hierarchical snapshot engine. In oneembodiment, hierarchical snapshot engine 152 can communicate withhierarchical asset history 154 and hierarchical snapshot data manager156 to utilize snapshot information to identify redundant, overlapping,and inconsistent snapshots hierarchical snapshot management program 200can remove or migrate within IT infrastructure environment 110.Hierarchical snapshot data manager 156 manages copies of snapshotmetadata for utilization in hierarchical snapshot manager 150. In oneembodiment, hierarchical snapshot data manger 156 analyzes andcorrelates snapshot information from hierarchical asset history 154.Hierarchical snapshot data manager 156 can communicate with hierarchicalasset history 154 to analyze snapshot information to determine duplicatesnapshots and inconsistent snapshots stored in hierarchical assethistory. Hierarchical snapshot manager 150 utilizes hierarchicalsnapshot management program 200 to migrate and consolidate snapshotsstored in IT infrastructure environment 110. Hierarchical snapshotmanagement program 200 is discussed in greater detail with regard toFIG. 2.

FIG. 2 is a flowchart depicting operational steps of hierarchicalsnapshot management program 200 in accordance with an exemplaryembodiment of the present invention.

In step 202, hierarchical snapshot management program 200 identifiessnapshots stored in an IT infrastructure environment. In one embodiment,hierarchical snapshot management program 200 accesses snapshot managers(i.e. layer 1 snapshot engine 120 and layer 2 snapshot engine 130) onlayers of IT infrastructure environment 110 in order to identifysnapshots. In an example, hierarchical snapshot management program 200accesses layer 1 snapshot manager 120 to identify the snapshots existingon layer 1 of IT infrastructure environment 110, and the snapshotinformation corresponding to each snapshot. The snapshot information caninclude at least in part the snapshot size, the creation time of thesnapshot, and the storage method and location of the snapshot. In thisexample, hierarchical snapshot management program 200 continues toaccess other layers of IT infrastructure environment 110, and identifiesexisting snapshots, and corresponding snapshot information. In oneembodiment, snapshot management program 200 determines relationships ofsnapshots in every layer of IT infrastructure environment 110, evenlayers that do not include a snapshot manager.

In step 204, hierarchical snapshot management program 200 determinespossible relationships between identified snapshots of the ITinfrastructure environment. In one embodiment, hierarchical snapshotmanagement program 200 utilizes the snapshots identified in step 202 anddetermines the possible snapshot relationships to IT infrastructureenvironment 110. In an example, hierarchical snapshot management program200 accesses snapshot data manager 124 and 134 and utilizes snapshotmetadata to determine relationships. The relationships hierarchicalsnapshot management program 200 determines include entities of ITinfrastructure environment 110 included in each snapshot, wherein theentities of the IT infrastructure environment can include storageelements, elements capable of creating snapshots, or other elements ofthe IT infrastructure environment. Data collection by hierarchicalsnapshot management program 200 can include all layers and elements ofIT infrastructure environment 110 having snapshots. In an example,hierarchical snapshot management program 200 identifies and correlatesrelationship data for snapshots corresponding to snapshots of layer 1snapshot manager 120 with a corresponding storage structure (i.e.virtual storage locations, separate physical disc storage) within ITinfrastructure environment 110. In this example, hierarchical snapshotmanagement program 200 repeats the identifying and correlating processfor each layer of IT infrastructure database 110. In one embodiment,relationship information that hierarchical snapshot management program200 uses to correlate the storage structure includes, but is not limitedto, snapshotted entities, layers that snapshotted entities relate to,parent entities of snapshotted entities, snapshots including a certainentity, and snapshot timestamps. A parent entity of a snapshotted entitycan be an entity within IT infrastructure environment 110 thatcontaining or controlling the snapshotted entity as a subsidiary. Invarious embodiments, parent entities have one or more correspondingchild entities. In examples with regard to IT infrastructure environment110, a snapshotted entity can have a relationship with a parent entity,wherein the parent entity contains the storage location of thesnapshotted entity, or can control the actions of the snapshottedentity. In some examples, determined relationships can relate to, layersof IT infrastructure environment 110 that store identified snapshots,entities of the IT infrastructure environment included in snapshots,relationships of snapshots to parent entities, snapshot timestamps, andsnapshot storage locations. The collection of determined relationshipsof existing snapshots results in a hierarchical organization of theentities of IT infrastructure environment 110.

In step 206, hierarchical snapshot management program 200 identifiesredundant snapshots, overlapping snapshots, and inconsistent snapshots.In one embodiment, hierarchical snapshot management program 200 utilizessnapshot metadata, snapshot information and relationship data toidentify redundant, overlapping, or inconsistent snapshots identified instep 202. Hierarchical snapshot management program 200 considerssnapshots to be redundant when a snapshot includes a parent entity thathas a relationship with another snapshot. In an example, a redundantsnapshot can be a snapshot including a storage device, wherein thestorage device contains another snapshot. Hierarchical snapshotmanagement program 200 considers snapshots to be overlapping whenseparate snapshots exist of an entity, and its parent entity. In anexample, if a snapshot of a portion of a storage device and a snapshotof the entire storage device exist, then the snapshots are overlapping.Hierarchical snapshot management program 200 considers snapshots to beinconsistent when a snapshotted entity has multiple parent entities, butfor one or more of the parent entities of the snapshotted entity, asnapshot does not exist, or the snapshots of the parent entities are nottaken simultaneously (i.e. do not have the same timestamps).

In step 208, hierarchical snapshot management program 200 consolidatesthe identified redundant, overlapping, and inconsistent snapshots. Inone embodiment, hierarchical snapshot management program 200consolidates snapshots by migrating snapshots and snapshot data, andremoving unnecessary snapshot data. Snapshots and snapshot datamigration can occur between different layers of IT infrastructureenvironment 110 in order to optimize the placement of snapshotsthroughout the IT infrastructure environment. In one embodiment,hierarchical snapshot management program 200 can migrate snapshots toparent entities and layers of IT infrastructure environment 110. Forexample, hierarchical snapshot management program 200 can migratesnapshots stored in storage devices on various layers of ITinfrastructure environment 110 to a single parent layer. In exemplaryembodiments, hierarchical snapshot management program 200 optimizes theplacement of snapshots throughout IT infrastructure environment 110 byplacing snapshots in certain layers of the IT infrastructureenvironment, minimizing storage space and complexity and providing anincrease in data security. In one embodiment, hierarchical snapshotmanagement program 200 compares data of redundant, overlapping orinconsistent snapshots to determine if snapshots are different from oneanother. Hierarchical snapshot management program 200 can remove theidentical portions of the snapshots in order to consolidate thesnapshots so that the snapshots are no longer redundant, overlapping orinconsistent. In one embodiment, hierarchical snapshot managementprogram 200 consolidates the redundant, overlapping and inconsistentsnapshots by generating updated snapshots not including unnecessary orrepetitive information, and removes snapshots having or includingunnecessary or repetitive information. In another embodiment,hierarchical snapshot management program 200 can output a reportdetailing the identified redundant, overlapping and inconsistentsnapshots. In an exemplary embodiment, hierarchical snapshot managementprogram 200 identifies the inconsistent snapshots (i.e. in a report),and allows for removal of the identified inconsistent snapshots.

In an example, multiple snapshots in a certain area of IT infrastructureenvironment 110 exist and have been taken at different times. In such anexample, a migration of the snapshots begins by assigning the oldestsnapshot to a storage virtualizer of IT infrastructure environment 110where hierarchical snapshot management program 200 creates and migratesa copy of the oldest snapshot to a storage device within ITinfrastructure environment. The migrated copy of the oldest snapshot hasa timestamp indicating the time the oldest snapshot was created, notwhen the copy was created. Once hierarchical snapshot management program200 creates and migrates a copy of a snapshot, the original snapshot canbe deleted. In this example, hierarchical snapshot management program200 migrates a newer snapshot (a snapshot in the same area of ITinfrastructure environment 110, but created at a later time) byassigning the newer snapshot to a storage virtualizer and associatingthe newer snapshot with the migrated copy of the oldest snapshot.Hierarchical snapshot management program 200 determines differentialdata between the newer snapshot and the migrated copy of the oldestsnapshot, and data from the newer snapshot not included in the migratedcopy of the oldest snapshot is added to the migrated copy of the oldestsnapshot to create an updated snapshot. The updated snapshot has atimestamp indicating the time at which the newer snapshot was created.Since hierarchical snapshot management program 200 utilizes differentialdata between the oldest snapshot and the newest snapshot to create theupdated current snapshot, the newer snapshot can be deleted. Themigration process repeats for all snapshots (oldest to newest), and theresult is hierarchical snapshot management program 200 generating acurrent snapshot for the certain area of IT infrastructure environment110 from all previous snapshots of that area that hierarchical snapshotmanagement program can update with subsequent snapshots.

FIG. 3 depicts a block diagram of components of computer 300, which isrepresentative of IT infrastructure environment 110, I/O system 140, andhierarchical snapshot manager 150, in accordance with an illustrativeembodiment of the present invention. It should be appreciated that FIG.3 provides only an illustration of one implementation and does not implyany limitations with regard to the environments in which differentembodiments may be implemented. Many modifications to the depictedenvironment may be made.

Computer 300 includes communications fabric 302, which providescommunications between computer processor(s) 304, memory 306, persistentstorage 308, communications unit 310, and input/output (I/O)interface(s) 312. Communications fabric 302 can be implemented with anyarchitecture designed for passing data and/or control informationbetween processors (such as microprocessors, communications and networkprocessors, etc.), system memory, peripheral devices, and any otherhardware components within a system. For example, communications fabric302 can be implemented with one or more buses.

Memory 306 and persistent storage 308 are computer-readable storagemedia. In this embodiment, memory 306 includes random access memory(RAM) 314 and cache memory 316. In general, memory 306 can include anysuitable volatile or non-volatile computer-readable storage media.Software and data 322 stored in persistent storage 308 for access and/orexecution by processor(s) 304 via one or more memories of memory 306.With respect to hierarchical snapshot manager 150, software and data 322includes hierarchical snapshot management program 200.

In this embodiment, persistent storage 308 includes a magnetic hard diskdrive. Alternatively, or in addition to a magnetic hard disk drive,persistent storage 308 can include a solid state hard drive, asemiconductor storage device, read-only memory (ROM), erasableprogrammable read-only memory (EPROM), flash memory, or any othercomputer-readable storage media that is capable of storing programinstructions or digital information.

The media used by persistent storage 308 may also be removable. Forexample, a removable hard drive may be used for persistent storage 308.Other examples include optical and magnetic disks, thumb drives, andsmart cards that are inserted into a drive for transfer onto anothercomputer-readable storage medium that is also part of persistent storage308.

Communications unit 310, in these examples, provides for communicationswith other data processing systems or devices. In these examples,communications unit 310 includes one or more network interface cards.Communications unit 310 may provide communications through the use ofeither or both physical and wireless communications links. Software anddata 322 may be downloaded to persistent storage 308 throughcommunications unit 310.

I/O interface(s) 312 allows for input and output of data with otherdevices that may be connected to computer 300. For example, I/Ointerface 312 may provide a connection to external devices 318 such as akeyboard, keypad, a touch screen, and/or some other suitable inputdevice. External devices 318 can also include portable computer-readablestorage media such as, for example, thumb drives, portable optical ormagnetic disks, and memory cards. Software and data 322 can be stored onsuch portable computer-readable storage media and can be loaded ontopersistent storage 308 via I/O interface(s) 312. I/O interface(s) 312also connect to a display 320.

Display 320 provides a mechanism to display data to a user and may be,for example, a computer monitor. Display 320 can also function as atouch screen, such as a display of a tablet computer.

The programs described herein are identified based upon the applicationfor which they are implemented in a specific embodiment of theinvention. However, it should be appreciated that any particular programnomenclature herein is used merely for convenience, and thus theinvention should not be limited to use solely in any specificapplication identified and/or implied by such nomenclature.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof code, which comprises one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat, in some alternative implementations, the functions noted in theblock may occur out of the order noted in the figures. For example, twoblocks shown in succession may, in fact, be executed substantiallyconcurrently, or the blocks may sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams and/or flowchart illustration, andcombinations of blocks in the block diagrams and/or flowchartillustration, can be implemented by special purpose hardware-basedsystems that perform the specified functions or acts, or combinations ofspecial purpose hardware and computer instructions.

What is claimed is:
 1. A method for snapshot management in a storageinfrastructure, the method comprising the steps of: a computeridentifying one or more snapshots within layers of the storageinfrastructure; the computer determining one or more relationships ofthe one or more identified snapshots of the storage infrastructure,wherein the relationships at least in part include relations of one ormore entities included in the one or more snapshots to additional one ormore entities in the one or more snapshots of the storageinfrastructure; the computer identifying one or more duplicate snapshotsutilizing the one or more determined relationships of the one moreidentified snapshots; and the computer consolidating the one or moreidentified duplicate snapshots.
 2. The method of claim 1, furthercomprising the steps of: the computer identifying one or moreinconsistent snapshots utilizing the one or more determinedrelationships of the one or more identified snapshots; and the computerconsolidating the one or more identified inconsistent snapshots.
 3. Themethod of claim 1, wherein said identifying the one or more snapshotswithin the layers of the storage infrastructure, comprises the step of:the computer accessing each layer of the storage infrastructure toidentify snapshots in each layer of the storage infrastructure.
 4. Themethod of claim 1, wherein the one or more identified duplicatesnapshots include one of the one or more snapshots including an entitycontaining another of the one or more snapshots, and the one of the oneor more snapshots and the another of the one or more snapshots aresubstantially similar.
 5. The method of claim 1, wherein the one or moreidentified inconsistent snapshots include snapshots of related entitiesnot having identical timestamps.
 6. The method of claim 2, wherein saidconsolidating the one or more identified duplicate snapshots and the oneor more identified inconsistent snapshots, further comprises the stepof: the computer migrating the one or more identified duplicatesnapshots and the one or more identified inconsistent snapshotsthroughout layers of the storage infrastructure in order to optimizeplacement of the one or more identified duplicate snapshots and the oneor more identified inconsistent snapshots in the storage infrastructure.7. The method of claim 6, further comprising the steps of: the computeridentifying repetitive information in the one or more identifiedduplicate snapshots and the one or more identified inconsistentsnapshots; and the computer generating one or more new snapshots withoutthe repetitive information.
 8. A computer program product for snapshotmanagement in a storage infrastructure, the computer program productcomprising: one or more computer-readable storage media and programinstructions stored on the one or more computer-readable storage media,the program instructions comprising: program instructions to identifyone or more snapshots within layers of the storage infrastructure;program instructions to determine one or more relationships of the oneor more identified snapshots of the storage infrastructure, wherein therelationships at least in part include relations of one or more entitiesincluded in the one or more snapshots to additional one or more entitiesin the one or more snapshots of the storage infrastructure; programinstructions to identify one or more duplicate snapshots utilizing theone or more determined relationships of the one more identifiedsnapshots; and program instructions to consolidate the one or moreidentified duplicate snapshots.
 9. The computer program product of claim8, further comprising program instructions to: identify one or moreinconsistent snapshots utilizing the one or more determinedrelationships of the one or more identified snapshots; and consolidatethe one or more identified inconsistent snapshots.
 10. The computerprogram product of claim 8, wherein said program instructions toidentify the one or more snapshots within the layers of the storageinfrastructure, comprise program instructions to: access each layer ofthe storage infrastructure to identify snapshots in each layer of thestorage infrastructure.
 11. The computer program product of claim 8,wherein the one or more identified duplicate snapshots include one ofthe one or more snapshots including an entity containing another of theone or more snapshots, and the one of the one or more snapshots and theanother of the one or more snapshots are substantially similar.
 12. Thecomputer program product of claim 8, wherein the one or more identifiedinconsistent snapshots include snapshots of related entities not havingidentical timestamps.
 13. The computer program product of claim 9,wherein said program instructions to consolidate the one or moreidentified duplicate snapshots and the one or more identifiedinconsistent snapshots, further comprises program instructions to:migrate the one or more identified duplicate snapshots and the one ormore identified inconsistent snapshots throughout layers of the storageinfrastructure in order to optimize placement of the one or moreidentified duplicate snapshots and the one or more identifiedinconsistent snapshots in the storage infrastructure.
 14. The computerprogram product of claim 13, further comprising program instructions to:identify repetitive information in the one or more identified duplicatesnapshots and the one or more identified inconsistent snapshots; andgenerate one or more new snapshots without the repetitive information.15. A computer system for snapshot management in a storageinfrastructure, the computer system comprising: one or more computerprocessors; one or more computer-readable storage media; programinstructions to identify one or more snapshots within layers of thestorage infrastructure; program instructions to determine one or morerelationships of the one or more identified snapshots of the storageinfrastructure, wherein the relationships at least in part includerelations of one or more entities included in the one or more snapshotsto additional one or more entities in the one or more snapshots of thestorage infrastructure; program instructions to identify one or moreduplicate snapshots utilizing the one or more determined relationshipsof the one more identified snapshots; and program instructions toconsolidate the one or more identified duplicate snapshots.
 16. Thecomputer system of claim 15, further comprising program instructions to:identify one or more inconsistent snapshots utilizing the one or moredetermined relationships of the one or more identified snapshots; andconsolidate the one or more identified inconsistent snapshots.
 17. Thecomputer system of claim 15, wherein said program instructions toidentify the one or more snapshots within the layers of the storageinfrastructure, comprise program instructions to: access each layer ofthe storage infrastructure to identify snapshots in each layer of thestorage infrastructure.
 18. The computer system of claim 15, wherein theone or more identified duplicate snapshots include one of the one ormore snapshots including an entity containing another of the one or moresnapshots, and the one of the one or more snapshots and the another ofthe one or more snapshots are substantially similar.
 19. The computersystem of claim 16, wherein said program instructions to consolidate theone or more identified duplicate snapshots and the one or moreidentified inconsistent snapshots, further comprises programinstructions to: migrate the one or more identified duplicate snapshotsand the one or more identified inconsistent snapshots throughout layersof the storage infrastructure in order to optimize placement of the oneor more identified duplicate snapshots and the one or more identifiedinconsistent snapshots in the storage infrastructure.
 20. The computersystem of claim 19, further comprising program instructions to: identifyrepetitive information in the one or more identified duplicate snapshotsand the one or more identified inconsistent snapshots; and generate oneor more new snapshots without the repetitive information.